From 56889787cfa77dfd96f0b3a3e6a4f26c2e4a5134 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Sat, 3 Sep 2011 18:22:38 -0400 Subject: ext4: improve handling of conflicting mount options If the user explicitly specifies conflicting mount options for delalloc or dioread_nolock and data=journal, fail the mount, instead of printing a warning and continuing (since many user's won't look at dmesg and notice the warning). Also, print a single warning that data=journal implies that delayed allocation is not on by default (since it's not supported), and furthermore that O_DIRECT is not supported. Improve the text in Documentation/filesystems/ext4.txt so this is clear there as well. Similarly, if the dioread_nolock mount option is specified when the file system block size != PAGE_SIZE, fail the mount instead of printing a warning message and ignoring the mount option. Signed-off-by: "Theodore Ts'o" --- Documentation/filesystems/ext4.txt | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'Documentation') diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt index 232a575a0c48..168242b5c045 100644 --- a/Documentation/filesystems/ext4.txt +++ b/Documentation/filesystems/ext4.txt @@ -160,7 +160,9 @@ noload if the filesystem was not unmounted cleanly, lead to any number of problems. data=journal All data are committed into the journal prior to being - written into the main file system. + written into the main file system. Enabling + this mode will disable delayed allocation and + O_DIRECT support. data=ordered (*) All data are forced directly out to the main file system prior to its metadata being committed to the @@ -419,8 +421,8 @@ written to the journal first, and then to its final location. In the event of a crash, the journal can be replayed, bringing both data and metadata into a consistent state. This mode is the slowest except when data needs to be read from and written to disk at the same time where it -outperforms all others modes. Currently ext4 does not have delayed -allocation support if this data journalling mode is selected. +outperforms all others modes. Enabling this mode will disable delayed +allocation and O_DIRECT support. /proc entries ============= -- cgit v1.2.1